1 files changed, 153 insertions, 0 deletions
diff --git a/libs/libgui/gui.c b/libs/libgui/gui.c
new file mode 100644
index 0000000..d8435e6
--- /dev/null
+++ b/libs/libgui/gui.c
@@ -0,0 +1,153 @@
+// MIT License, Copyright (c) 2021 Marvin Borner
+
+#include <assert.h>
+#include <def.h>
+#include <errno.h>
+#include <libgui/gui.h>
+#include <libgui/msg.h>
+#include <list.h>
+#include <print.h>
+
+#define WM_PATH "/bin/wm"
+
+struct gui_window {
+	u32 id;
+	struct context ctx;
+};
+
+struct list *windows = NULL;
+
+static struct gui_window *win_by_id(u32 id)
+{
+	assert(windows);
+	struct node *iterator = windows->head;
+	while (iterator) {
+		struct gui_window *win = iterator->data;
+		if (win->id == id)
+			return iterator->data;
+		iterator = iterator->next;
+	}
+	return NULL;
+}
+
+/**
+ * GFX wrappers
+ */
+
+static res fill(u32 id, u32 c)
+{
+	struct gui_window *win = win_by_id(id);
+	if (!win)
+		return -ENOENT;
+	gfx_fill(&win->ctx, c);
+	return EOK;
+}
+
+/**
+ * Program interface
+ */
+
+res gui_new_window(void)
+{
+	if (!windows)
+		windows = list_new();
+
+	struct gui_window *win = zalloc(sizeof(*win));
+
+	struct message_new_window msg = { .header.state = MSG_NEED_ANSWER };
+	if (msg_send(pidof(WM_PATH), GUI_NEW_WINDOW, &msg, sizeof(msg)) > 0 &&
+	    msg_receive(&msg, sizeof(msg)) > 0 &&
+	    msg.header.type == (GUI_NEW_WINDOW | MSG_SUCCESS)) {
+		win->id = msg.id;
+		win->ctx = msg.ctx;
+		u32 size;
+		res ret = shaccess(msg.shid, (u32 *)&win->ctx.fb, &size);
+		if (ret < 0 || !win->ctx.fb)
+			return MIN(ret, -EFAULT);
+		list_add(windows, win);
+		assert(fill(win->id, COLOR_BLACK) == EOK);
+		gui_redraw_window(win->id);
+		return win->id;
+	}
+	return -EINVAL;
+}
+
+res gui_redraw_window(u32 id)
+{
+	struct message_redraw_window msg = { .id = id, .header.state = MSG_NEED_ANSWER };
+	if (msg_send(pidof(WM_PATH), GUI_REDRAW_WINDOW, &msg, sizeof(msg)) > 0 &&
+	    msg_receive(&msg, sizeof(msg)) > 0 &&
+	    msg.header.type == (GUI_REDRAW_WINDOW | MSG_SUCCESS))
+		return id;
+	return -EINVAL;
+}
+
+/**
+ * Message handling
+ */
+
+static res handle_error(const char *op, res code)
+{
+	log("GUI error at '%s': %s (%d)\n", op, strerror(code), code);
+	return code;
+}
+
+static res handle_ping(struct message_ping *msg)
+{
+	if (msg->ping != MSG_PING_SEND)
+		return handle_error("ping", EINVAL);
+
+	msg->header.type |= MSG_SUCCESS;
+	msg->ping = MSG_PING_RECV;
+	msg_send(msg->header.src, GUI_PING, &msg, sizeof(msg));
+
+	return errno;
+}
+
+static res handle_mouse(struct message_mouse *msg)
+{
+	if (msg->header.state == MSG_NEED_ANSWER)
+		msg_send(msg->header.src, msg->header.type | MSG_SUCCESS, msg, sizeof(*msg));
+
+	return errno;
+}
+
+static void handle_exit(void)
+{
+	if (!windows)
+		return;
+
+	struct node *iterator = windows->head;
+	while (iterator) {
+		struct gui_window *win = iterator->data;
+		struct message_destroy_window msg = { .id = win->id };
+		msg_send(pidof(WM_PATH), GUI_DESTROY_WINDOW, &msg, sizeof(msg));
+		iterator = iterator->next;
+	}
+
+	list_destroy(windows);
+}
+
+/**
+ * Main loop
+ */
+
+void gui_loop(void)
+{
+	atexit(handle_exit);
+
+	void *msg = zalloc(4096);
+	while (msg_receive(msg, 4096)) {
+		struct message_header *head = msg;
+		switch (head->type) {
+		case GUI_PING:
+			handle_ping(msg);
+			break;
+		case GUI_MOUSE:
+			handle_mouse(msg);
+			break;
+		default:
+			handle_error("loop", EINVAL);
+		}
+	}
+}